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Math Help - Binomial Distribution

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    Binomial Distribution

    Explain whether or not a binomial distribution is a suitable model for the random variable.

    (a) the number of tosses of a fair coin before the coin lands 'head'

    (b) the score a pupil gets in answering 10 true/false questions with 1 mark for a correct answer and -1 for a wrong answer

    (c) the number of rainy days in a randomly chosen week at a certain place for which weather records show that it rains on 40% of the days
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    Quote Originally Posted by acc100jt View Post
    Explain whether or not a binomial distribution is a suitable model for the random variable.

    (a) the number of tosses of a fair coin before the coin lands 'head'

    (b) the score a pupil gets in answering 10 true/false questions with 1 mark for a correct answer and -1 for a wrong answer

    (c) the number of rainy days in a randomly chosen week at a certain place for which weather records show that it rains on 40% of the days
    Apply the three criteria for a binomial distribution to each of the given random variables.
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    (a) No. The number of trials if not fixed.

    (b) No. If I let X be the number of questions answered correctly, then X~Bin(10,0.5)
    but the marks obtained (Y) is given by Y=(1)X+(-1)(10-X)=2X-10 is NOT a binomial

    (c) Maybe....the probability that probability that it rains might not be the same due to seasons.

    Am I correct?
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